Automatic light adjustment camera and exchangable lenses therefor

Abstract

An automatic light adjustment camera comprises a flash apparatus capable of performing preliminary flash emission and main flash emission; a photometric device for dividing the light beam emitted from the flash apparatus and reflected by a field into a plurality of photometric areas for photometry and outputting each photometric value; a light adjusting area determining device for determining the photometric areas which are allowed to contribute to light adjustment at the time of the main flash emission using the photometric values, photographing distances, and detection errors for the photographing distances at the time of preliminary flash emission; and a light adjusting device for performing light adjustment at the time of the main flash emission using the light adjusting areas determined by the light adjusting area determining device.

What is claimed is: 
     
       1. An automatic light adjustment camera including the following: flashing means capable of performing preliminary flash emission and main flash emission;   photometric means for dividing the light beam emitted from said flashing means and reflected by a field into a plurality of photometric areas for photometry and outputting each photometric value;   light adjusting area determining means for determining at least one photometric area which is allowed to contribute to light adjustment at the time of said main flash emission on the basis of said photometric values, at the time of preliminary flash emission, a photographing distance, and at least one detection error for said photographing distance; and   light adjusting means for performing light adjustment at the time of said main flash emission on the basis of said at least one light adjusting area determined by said light adjusting area determining means.   
     
     
       2. An automatic light adjustment camera according to claim 1, wherein said light adjusting area determining means uses the photographing distance detected by photographing distance detecting means provided in a mounted photometric lens.   
     
     
       3. An automatic light adjustment camera according to claim 1, wherein said light adjusting area determining means uses said at least one detection error which is output from storage means provided in a mounted photometric lens in accordance with the photographing distances.   
     
     
       4. An automatic light adjustment camera according to claim 3, wherein said light adjusting area determining means uses said at least one detection error which is output from storage means provided in a mounted zoom lens in accordance with photographing distance and a focal length.   
     
     
       5. An automatic light adjustment camera according to claim 3, wherein said light adjusting area determining means uses both long distance side error and short distance side error for the nominal value of photographing distance which is output from storage means provided in a mounted photometric lens.   
     
     
       6. An automatic light adjustment camera according to claim 5, wherein said light adjusting area determining means calculates a first given amount for determining whether such amount should be allowed to contribute to said light adjustment or not on the basis of said short distance side and at the same time, makes the photometric area having a photometric value at the time of preliminary flash emission which exceeds said first given amount an area which is not allowed to contribute to the light adjustment.   
     
     
       7. An automatic light adjustment camera according to claim 5, wherein said light adjusting area determining means calculates a second given amount for determining whether such amount should be allowed to contribute to said light adjustment or not on the basis of said long distance side and at the same time, makes the photometric area having a photometric value at the time of preliminary flash emission which exceeds said second given amount an area which is not allowed to contribute to the light adjustment.   
     
     
       8. An automatic light adjustment camera according to claim 1, wherein said light adjusting area determining means performs said determination in such a manner that the greater the detection error for said photographing distance, the higher is the probability that the respective photometric area is allowed to contribute to said light adjustment.   
     
     
       9. An automatic light adjustment camera according to claim 1, wherein said light adjusting area determining means uses said at least one error at the time of focus detection.   
     
     
       10. An automatic light adjustment camera according to claim 9, wherein said at least one error at the time of focus detection is determined in accordance with photographing distance and a focal length.   
     
     
       11. A photographic exchangeable lens mountable on an automatic light adjustment camera according to claim 1, including the following: detection means for detecting the photographing distances;   storage means for storing in advance said at least one detection error which correspond to the photographing distances.   
     
     
       12. A photographic exchangeable lens according to claim 11, wherein said exchangeable lens is capable of varying its focal lengths, and in said storage means, said at least one error which corresponds to the focal length and the photographing distance is stored.   
     
     
       13. A photographic exchangeable lens according to claim 11, wherein there are stored in said storage means the long distance side error and short distance side error for the nominal values of the photographing distances.